Custom errors for when Email is invalid via SSO

app/controllers/session_controller.rb

@@ -129,6 +129,7 @@ class SessionController < ApplicationController
         render_sso_error(text: I18n.t("sso.not_found"), status: 500)
       end
     rescue ActiveRecord::RecordInvalid => e
+
       if SiteSetting.verbose_sso_logging
         Rails.logger.warn(<<-EOF)
           Verbose SSO log: Record was invalid: #{e.record.class.name} #{e.record.id}\n
@@ -137,7 +138,17 @@ class SessionController < ApplicationController
           #{sso.diagnostics}
         EOF
       end
-      render_sso_error(text: I18n.t("sso.unknown_error"), status: 500)
+
+
+      text = nil
+
+      # If there's a problem with the email we can explain that
+      if (e.record.is_a?(User) && e.record.errors[:email].present?)
+        text = e.record.email.blank? ? I18n.t("sso.no_email") : I18n.t("sso.email_error")
+      end
+
+      render_sso_error(text: text || I18n.t("sso.unknown_error"), status: 500)
+
     rescue => e
       message = "Failed to create or lookup user: #{e}."
       message << "\n\n" << "-" * 100 << "\n\n"

app/views/session/sso_login.html.erb

@@ -1,2 +1,5 @@
-<h1><%= @sso_error %></h1>
+<h1><%=t 'sso.login_error' %></h1>
 
+<br/>
+
+<p><%= @sso_error %></p>

config/locales/server.en.yml

@@ -1544,10 +1544,13 @@ en:
       user: 'Users'
 
   sso:
+    login_error: "Login Error"
     not_found: "Your account couldn't be found. Please contact the site's administrator."
     account_not_approved: "Your account is pending approval. You will receive an email notification when you are approved."
     unknown_error: "There is a problem with your account. Please contact the site's administrator."
     timeout_expired: "Account login timed out, please try logging in again."
+    no_email: "No email address was provided. Please contact the site's administrator."
+    email_error: "An account could not be registered with that email address. Please contact the site's administrator."
 
   original_poster: "Original Poster"
   most_posts: "Most Posts"